What unsustainable behavior needs to change: In 2013 when the Green Party in Germany demanded a veggie/vegan day in company, school or university canteens, the outcry was massive: “Cancel culture.” “Don’t take away our freedom!” “Political paternalism!”. The idea was not only to create awareness for a diet with less meat but to directly reduce emissions.
However we need to recognize that meat consumption is a big driver for CO2 emissions that expedites global warming. Western Europeans eat 10x more meat than people living in India. Eating meat has societal as well as personal consequences: A fat-heavy diet often leads to obesity and severe health issues like heart attacks.
The problem: most often the negative externalities of meat consumption are hidden. Most people don’t know how much CO2 emission their steak is responsible for how a meat dish compares to a veggie option.
So the question is: how can we become choice architects that just nudges a decision instead of telling people what to do.
The Green Nudge: In a joint effort the Ludwig-Maximilians-Universität München, Humboldt-Universität zu Berlin and the Aalto University wanted to examine if making negative environmental impacts like CO2 emissions more salient, would nudge people to adapt their choices.
In a 10 day field experiment in one of the biggest university canteens in Munich with over 8.000 visitors (during that 10 day time period), the researchers introduced menu displays showing the food option but also the environmental externalities like the CO2 footprint
The interesting bit: their experimental design included testing different options of how to visualize the negative footprint.
➡ the negative cost in €
➡ the amount of an individual’s daily CO2 budget spent
➡ the amount of CO2 emissions
They introduced traffic light colors: green for dishes with low CO2 emissions, yellow for more emissions and red for the “climate-killer-lunch”.
The result: the demand decreased for CO2-intensive choices with meat and fish and thus reduced the footprint of the total lunch menu. The researchers could observe the biggest effect when visitors learned how much environmental cost (in €) their lunch would cause. So making something intangible more salient resulted in almost 10% less CO2 emissions compared to days when they didn’t show any negative environmental impact on the menu displays.